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I have raw data of Gyroscope and magnetometer. on basis of this data, i have to calculate Heading information with an accuracy of 1Deg.

I would like to know, is there any algorithm which can help me to get heading info using available information with mentioned accuracy?

Any article or any link also will be helpful.

Thanks

Pratik
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    stackoverflow isn't about searching/writing code for you, it's about fixing issues you have in your [existing] code. Show us what you have tried so far and programmers here would be able to help you, otherwise I only can suggest you to [search with google](https://www.google.com.ua/search?q=calculate+heading+from+Gyroscope+and+magnetometer+data) (or just look at the sidebar under the _Related_ section) and stop wasting our time doing searching for you – ankhzet Jan 28 '16 at 12:31
  • The question is too broad in its current form. What algorithm(s) did you try, and where exactly did you get stuck? Note that requests for off-site resources are considered off-topic here. – njuffa Jan 28 '16 at 20:38
  • Check out yaw returned by Phone's motion API – nbsrujan Jan 29 '16 at 09:03

1 Answers1

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I am assuming you are using phone to collect gyroscope+magnetometer data.

You cannot calculate Heading with Gyro+Magnetometer unless you know initial state of device. You have to try Accelerometer+Magnetometer. You can get heading values from rotation-matrix' oryaw` component from Motion sensor API of Android/IOS device.

If you want to implement of your own try tilt-compensation algorithm. All you have to do is implement tilt- compensated ecompass using accelerometer and magnetometer. You get accelerometer and magnetometer readings in device frame. Accelerometer and Magnetometer gives readings as a function of rotation of device. This rotation contains information of Roll, Pitch and Heading of device. Following is explanation and derivation of heading estimation using accelerometer+magnetometer.

Android sensor coordinate system

Tilt compensation algorithm

Let accelerometer and magnetometer give you

readings respectively. They are in device frame, and device is rotated through

.

Where is heading you are looking for. So rotation matrix of device will be

We have to solve for . So step by step solving for .

From above, equating to zero we get

Having from above

This is basic method of obtaining Heading value from accelerometer+magentomete. Yaw/Heading value is provided by Motion sensor APIs present in mobile phones.

You have to look at few things while implementing sensor-fusion algorithms. Accelerometers doesn't always gravity direction, it gives direction of ovarall acceleration experienced by the sensor eg, devices under linear accelerations. Magnetometer readings are subjected distortion due to ferromagnetic substances in vicinity. Accuracy depends on systematic bias component in gyroscope sensor too.

There are numerous algorithms to estimate accurate heading values. Some of them are

nbsrujan
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  • thank you for your detailed answer. I forgot to mention about my application in my question. My application is related to aviation field. My magnetometer will be located on aircraft vertical fin. I will try this approach also – Pratik Jan 29 '16 at 11:26
  • @Pratik If magnetometer is located on aircraft fin, check out Magnetometer readings once. You have to calibrate keeping magnetometer before you use it, if sensor doesn't calibrate by itself. – nbsrujan Feb 01 '16 at 15:33